This invention generally relates to the art of electrical connectors and, particularly, to an electrical connector assembly which incorporates an improved terminal position assurance (TPA) system that not only detects an incompletely inserted terminal but also locks a properly inserted terminal in its fully inserted position.
Generally, an electrical connector includes a dielectric housing mounting at least one electrically conductive terminal. The terminal is electrically connected to another circuit component, such as a discrete electrical wire. Connectors often are employed in mateable pairs such that each terminal and the housing of one connector are mateable with a corresponding terminal and the housing of a complementary mating connector.
Electrical connector assemblies are used in a wide variety of applications where it is necessarily to electrically interconnect a plurality of electrical wires to perform various functions. The terminals of electrical connectors frequently are small components, such as terminals that are stamped and/or formed from thin sheet metal material. A poor quality electrical connection may occur if one (or more) terminal is not properly seated in its respective housing. The improper seating of a terminal in a housing may occur if the terminal is not fully inserted into the housing during the initial assembly of the connector or if the terminal is vibrated or pulled out of its fully seated condition during use of the connector. A pulling force on an electrical wire secured to a terminal may cause a temporary break in the electrical contact between the terminal and another terminal of the mating connector.
More severe pulling forces on the electrical wire and/or the terminal may cause a partial or complete disconnection. In either event, even a momentary break in the electrical connection may result in spurious operation of an electrically driven device or an electrical circuit associated with the connector. Consequently, various locking structures have been used to lock terminals in their respective connector housings. Typically, the locking structure may include resilient tangs or latch projections which engage shoulders on the connector housing. Unfortunately, such resilient tangs or latch projections are prone to breakage. In addition, they do not detect or indicate whether or not a terminal is fully inserted and seated in the connector housing.
To avoid these problems, it often is required to provide connectors with some form of a terminal position assurance (TPA) system to detect incomplete insertion of the terminals. In some applications, the TPA system or device also performs the function of locking the terminals in the connector housing.
Heretofore, many TPA systems use separate TPA xe2x80x9ckeysxe2x80x9d which arc insertable into openings in the connector housing to detect full insertion of the terminals and to lock the terminals in their fully inserted positions. For dual row connector designs, a pair of TPA keys may be required. Such TPA keys create problems in that they require additional and costly manufacture and assembly. Separate TPA keys require additional components to be held in inventory. In addition, such TPA keys are prone to be lost or misplaced. Even if the TPA keys are tethered to the housing, such as by a living hinge, such TPA keys often are broken off from the tether or otherwise damaged. Regardless of whether the TPA keys are separate or tethered, they are inserted into the connector housing through an opening in the outer housing surface. These openings create further problems in electrical leakage and also may be dangerous for an operator during assembly and use.
The present invention is directed to solving this myriad of problems by providing a unique TPA system which employs totally internal components within a multi-part connector housing.
An object, therefore, of the invention is to provide an electrical connector assembly with a new and improved terminal position assurance (TPA) system.
In the exemplary embodiment of the invention, the electrical connector assembly includes a connector housing having a pair of interconnectable housing portions. Each housing portion has a terminal-receiving passage. A conductive terminal is inserted into the passage of each housing portion. An opening is provided in each housing portion communicating with the respective terminal-receiving passage thereof. A locking projection on each housing portion is insertable into the opening of the other housing portion to a position preventing withdrawal of the terminal of the other housing portion when the housing portions are interconnected.
As disclosed herein, the housing portions are hermaphroditic. Each housing portion has a pair of the openings on opposite sides of the respective terminal for receiving a pair of the locking projections of the other housing portion in positions on opposite sides of the terminal preventing withdrawal thereof.
According to one aspect of the invention, each housing portion includes a flexible locking arm adjacent the opening in the respective housing portion. The flexible locking arm is engageable with a locking shoulder on the respective terminal. The locking projection on the other housing portion is insertable to a position behind the flexible locking arm to prevent the locking arm from moving out of engagement with the locking shoulder on the respective terminal.
According to another aspect of the invention, the terminal in each housing portion includes a locking shoulder. The locking projection of the other housing portion is insertable to a position behind the locking shoulder to prevent withdrawal of the respective terminal.
Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings.